High Intensity Focused Ultrasound Treatment for Tremor

HIFU stands for Hight Intensity Focused Ultrasound. During HIFU, multiple ultrasound beams are focused to a targeted area in the brain and is used to treat a number of diseases. It’s a minimally invasive technique that does not involve any incisions. You may have also heard it referred to as focused ultrasound or MR-guided focused ultrasound.

HIFU is FDA-approved to treat essential tremor and a tremor-dominant Parkinson's disease. More specifically, it is used to treat the shaking and trembling of the hands, head and voice that can be so troublesome and sometimes debilitating for people with these two neurological conditions.

Every patient is different, but in general, patients who undergo HIFU are expected to get at least a 50% reduction in their tremor. Most individuals typically get even better results, achieving a 70 to 80% reduction in tremor on the treated side of the body after one procedure.

HIFU is an option for patients whose tremor has not been effectively controlled with medications or for those who experience negative side effects from medications. Most patients are advised to work with a neurologist, and if possible, a neurologist who specializes in movement disorders.

Additionally, in order for the high intensity ultrasound to work, it needs to penetrate through the skull, so patients must undergo pre-procedure testing to evaluate the thickness of their skull. Most individuals are appropriate candidates for the treatment, but there are some who don’t qualify.

• On the day of the treatment, the patient has their head shaved in order for the ultrasound waves to effectively travel through the skull. Just prior to the procedure, the patient receives IV medication to help with any discomfort and prevent nausea.
• In the pre-op area, the patient will have a frame placed on their head. This is used for guidance of the ultrasound beams. Once inside the specially equipped MRI suite where the procedure is performed, a dome or helmet-like device that is filled with cold water is placed over the top of their head and attached to the frame. This is the mechanism that the ultrasound will be conducted through for the treatment.
• An initial MRI is performed to make sure that we are targeting the precise location where the ultrasound is to be focused, and then a lower intensity dose of ultrasound is administered. That allows us to test the degree of tremor reduction and to make sure we are hitting the precise location, and to check for any side effects. Once the test dose accuracy and effect are confirmed, we move ahead to the full procedure, which generally lasts 1-2 hours.

After the treatment is finished, patients return to the post-op area and are monitored to ensure they're not experiencing side effects from the pre-sedation or the pre-procedure medications. Then the head frame is removed, and the patient can get up to walk and move around. HIFU is generally performed on an outpatient basis, so most patients go home the same day.

Patients may experience temporary neurologic changes including imbalance or numbness of the face, arm or leg that will improve over the course of weeks after the procedure.

After their HIFU procedure, most patients see immediate results. Many leave the hospital with a much greater stability in their arm movements due to the reduced hand tremor.